src/plugins/nat/out2in_ed.c

   1 /*
   2  * Copyright (c) 2018 Cisco and/or its affiliates.
   3  * Licensed under the Apache License, Version 2.0 (the "License");
   4  * you may not use this file except in compliance with the License.
   5  * You may obtain a copy of the License at:
   6  *
   7  *     http://www.apache.org/licenses/LICENSE-2.0
   8  *
   9  * Unless required by applicable law or agreed to in writing, software
  10  * distributed under the License is distributed on an "AS IS" BASIS,
  11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12  * See the License for the specific language governing permissions and
  13  * limitations under the License.
  14  */
  15 /**
  16  * @file
  17  * @brief NAT44 endpoint-dependent outside to inside network translation
  18  */
  19
  20 #include <vlib/vlib.h>
  21 #include <vnet/vnet.h>
  22 #include <vnet/pg/pg.h>
  23 #include <vnet/ip/ip.h>
  24 #include <vnet/ethernet/ethernet.h>
  25 #include <vnet/fib/ip4_fib.h>
  26 #include <vnet/udp/udp.h>
  27 #include <vppinfra/error.h>
  28 #include <nat/nat.h>
  29 #include <nat/nat_ipfix_logging.h>
  30 #include <nat/nat_reass.h>
  31 #include <nat/nat_inlines.h>
  32 #include <nat/nat_syslog.h>
  33 #include <nat/nat_ha.h>
  34
  35 static char *nat_out2in_ed_error_strings[] = {
  36 #define _(sym,string) string,
  37   foreach_nat_out2in_ed_error
  38 #undef _
  39 };
  40
  41 typedef struct
  42 {
  43   u32 sw_if_index;
  44   u32 next_index;
  45   u32 session_index;
  46   u32 is_slow_path;
  47 } nat44_ed_out2in_trace_t;
  48
  49 static u8 *
  50 format_nat44_ed_out2in_trace (u8 * s, va_list * args)
  51 {
  52   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  53   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  54   nat44_ed_out2in_trace_t *t = va_arg (*args, nat44_ed_out2in_trace_t *);
  55   char *tag;
  56
  57   tag =
  58     t->is_slow_path ? "NAT44_OUT2IN_ED_SLOW_PATH" :
  59     "NAT44_OUT2IN_ED_FAST_PATH";
  60
  61   s = format (s, "%s: sw_if_index %d, next index %d, session %d", tag,
  62               t->sw_if_index, t->next_index, t->session_index);
  63
  64   return s;
  65 }
  66
  67 static inline u32
  68 icmp_out2in_ed_slow_path (snat_main_t * sm, vlib_buffer_t * b0,
  69                           ip4_header_t * ip0, icmp46_header_t * icmp0,
  70                           u32 sw_if_index0, u32 rx_fib_index0,
  71                           vlib_node_runtime_t * node, u32 next0, f64 now,
  72                           u32 thread_index, snat_session_t ** p_s0)
  73 {
  74   next0 = icmp_out2in (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
  75                        next0, thread_index, p_s0, 0);
  76   snat_session_t *s0 = *p_s0;
  77   if (PREDICT_TRUE (next0 != NAT_NEXT_DROP && s0))
  78     {
  79       /* Accounting */
  80       nat44_session_update_counters (s0, now,
  81                                      vlib_buffer_length_in_chain
  82                                      (sm->vlib_main, b0), thread_index);
  83       /* Per-user LRU list maintenance */
  84       nat44_session_update_lru (sm, s0, thread_index);
  85     }
  86   return next0;
  87 }
  88
  89 #ifndef CLIB_MARCH_VARIANT
  90 int
  91 nat44_o2i_ed_is_idle_session_cb (clib_bihash_kv_16_8_t * kv, void *arg)
  92 {
  93   snat_main_t *sm = &snat_main;
  94   nat44_is_idle_session_ctx_t *ctx = arg;
  95   snat_session_t *s;
  96   u64 sess_timeout_time;
  97   nat_ed_ses_key_t ed_key;
  98   clib_bihash_kv_16_8_t ed_kv;
  99   int i;
 100   snat_address_t *a;
 101   snat_session_key_t key;
 102   snat_main_per_thread_data_t *tsm = vec_elt_at_index (sm->per_thread_data,
 103                                                        ctx->thread_index);
 104
 105   s = pool_elt_at_index (tsm->sessions, kv->value);
 106   sess_timeout_time = s->last_heard + (f64) nat44_session_get_timeout (sm, s);
 107   if (ctx->now >= sess_timeout_time)
 108     {
 109       ed_key.l_addr = s->in2out.addr;
 110       ed_key.r_addr = s->ext_host_addr;
 111       ed_key.fib_index = s->in2out.fib_index;
 112       if (snat_is_unk_proto_session (s))
 113         {
 114           ed_key.proto = s->in2out.port;
 115           ed_key.r_port = 0;
 116           ed_key.l_port = 0;
 117         }
 118       else
 119         {
 120           ed_key.proto = snat_proto_to_ip_proto (s->in2out.protocol);
 121           ed_key.l_port = s->in2out.port;
 122           ed_key.r_port = s->ext_host_port;
 123         }
 124       if (is_twice_nat_session (s))
 125         {
 126           ed_key.r_addr = s->ext_host_nat_addr;
 127           ed_key.r_port = s->ext_host_nat_port;
 128         }
 129       ed_kv.key[0] = ed_key.as_u64[0];
 130       ed_kv.key[1] = ed_key.as_u64[1];
 131       if (clib_bihash_add_del_16_8 (&tsm->in2out_ed, &ed_kv, 0))
 132         nat_elog_warn ("in2out_ed key del failed");
 133
 134       if (snat_is_unk_proto_session (s))
 135         goto delete;
 136
 137       snat_ipfix_logging_nat44_ses_delete (ctx->thread_index,
 138                                            s->in2out.addr.as_u32,
 139                                            s->out2in.addr.as_u32,
 140                                            s->in2out.protocol,
 141                                            s->in2out.port,
 142                                            s->out2in.port,
 143                                            s->in2out.fib_index);
 144
 145       nat_syslog_nat44_sdel (s->user_index, s->in2out.fib_index,
 146                              &s->in2out.addr, s->in2out.port,
 147                              &s->ext_host_nat_addr, s->ext_host_nat_port,
 148                              &s->out2in.addr, s->out2in.port,
 149                              &s->ext_host_addr, s->ext_host_port,
 150                              s->in2out.protocol, is_twice_nat_session (s));
 151
 152       nat_ha_sdel (&s->out2in.addr, s->out2in.port, &s->ext_host_addr,
 153                    s->ext_host_port, s->out2in.protocol, s->out2in.fib_index,
 154                    ctx->thread_index);
 155
 156       if (is_twice_nat_session (s))
 157         {
 158           for (i = 0; i < vec_len (sm->twice_nat_addresses); i++)
 159             {
 160               key.protocol = s->in2out.protocol;
 161               key.port = s->ext_host_nat_port;
 162               a = sm->twice_nat_addresses + i;
 163               if (a->addr.as_u32 == s->ext_host_nat_addr.as_u32)
 164                 {
 165                   snat_free_outside_address_and_port (sm->twice_nat_addresses,
 166                                                       ctx->thread_index,
 167                                                       &key);
 168                   break;
 169                 }
 170             }
 171         }
 172
 173       if (snat_is_session_static (s))
 174         goto delete;
 175
 176       snat_free_outside_address_and_port (sm->addresses, ctx->thread_index,
 177                                           &s->out2in);
 178     delete:
 179       nat44_delete_session (sm, s, ctx->thread_index);
 180       return 1;
 181     }
 182
 183   return 0;
 184 }
 185 #endif
 186
 187 static snat_session_t *
 188 create_session_for_static_mapping_ed (snat_main_t * sm,
 189                                       vlib_buffer_t * b,
 190                                       snat_session_key_t l_key,
 191                                       snat_session_key_t e_key,
 192                                       vlib_node_runtime_t * node,
 193                                       u32 thread_index,
 194                                       twice_nat_type_t twice_nat,
 195                                       lb_nat_type_t lb_nat, f64 now)
 196 {
 197   snat_session_t *s;
 198   snat_user_t *u;
 199   ip4_header_t *ip;
 200   udp_header_t *udp;
 201   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 202   clib_bihash_kv_16_8_t kv;
 203   snat_session_key_t eh_key;
 204   nat44_is_idle_session_ctx_t ctx;
 205
 206   if (PREDICT_FALSE (maximum_sessions_exceeded (sm, thread_index)))
 207     {
 208       b->error = node->errors[NAT_OUT2IN_ED_ERROR_MAX_SESSIONS_EXCEEDED];
 209       nat_elog_notice ("maximum sessions exceeded");
 210       return 0;
 211     }
 212
 213   u = nat_user_get_or_create (sm, &l_key.addr, l_key.fib_index, thread_index);
 214   if (!u)
 215     {
 216       nat_elog_warn ("create NAT user failed");
 217       return 0;
 218     }
 219
 220   s = nat_ed_session_alloc (sm, u, thread_index, now);
 221   if (!s)
 222     {
 223       nat44_delete_user_with_no_session (sm, u, thread_index);
 224       nat_elog_warn ("create NAT session failed");
 225       return 0;
 226     }
 227
 228   ip = vlib_buffer_get_current (b);
 229   udp = ip4_next_header (ip);
 230
 231   s->ext_host_addr.as_u32 = ip->src_address.as_u32;
 232   s->ext_host_port = e_key.protocol == SNAT_PROTOCOL_ICMP ? 0 : udp->src_port;
 233   s->flags |= SNAT_SESSION_FLAG_STATIC_MAPPING;
 234   if (lb_nat)
 235     s->flags |= SNAT_SESSION_FLAG_LOAD_BALANCING;
 236   if (lb_nat == AFFINITY_LB_NAT)
 237     s->flags |= SNAT_SESSION_FLAG_AFFINITY;
 238   s->flags |= SNAT_SESSION_FLAG_ENDPOINT_DEPENDENT;
 239   s->out2in = e_key;
 240   s->in2out = l_key;
 241   s->in2out.protocol = s->out2in.protocol;
 242   user_session_increment (sm, u, 1);
 243
 244   /* Add to lookup tables */
 245   make_ed_kv (&kv, &e_key.addr, &s->ext_host_addr, ip->protocol,
 246               e_key.fib_index, e_key.port, s->ext_host_port);
 247   kv.value = s - tsm->sessions;
 248   ctx.now = now;
 249   ctx.thread_index = thread_index;
 250   if (clib_bihash_add_or_overwrite_stale_16_8 (&tsm->out2in_ed, &kv,
 251                                                nat44_o2i_ed_is_idle_session_cb,
 252                                                &ctx))
 253     nat_elog_notice ("out2in-ed key add failed");
 254
 255   if (twice_nat == TWICE_NAT || (twice_nat == TWICE_NAT_SELF &&
 256                                  ip->src_address.as_u32 == l_key.addr.as_u32))
 257     {
 258       eh_key.protocol = e_key.protocol;
 259       if (snat_alloc_outside_address_and_port (sm->twice_nat_addresses, 0,
 260                                                thread_index, &eh_key,
 261                                                sm->port_per_thread,
 262                                                tsm->snat_thread_index))
 263         {
 264           b->error = node->errors[NAT_OUT2IN_ED_ERROR_OUT_OF_PORTS];
 265           nat44_delete_session (sm, s, thread_index);
 266           if (clib_bihash_add_del_16_8 (&tsm->out2in_ed, &kv, 0))
 267             nat_elog_notice ("out2in-ed key del failed");
 268           return 0;
 269         }
 270       s->ext_host_nat_addr.as_u32 = eh_key.addr.as_u32;
 271       s->ext_host_nat_port = eh_key.port;
 272       s->flags |= SNAT_SESSION_FLAG_TWICE_NAT;
 273       make_ed_kv (&kv, &l_key.addr, &s->ext_host_nat_addr, ip->protocol,
 274                   l_key.fib_index, l_key.port, s->ext_host_nat_port);
 275     }
 276   else
 277     {
 278       make_ed_kv (&kv, &l_key.addr, &s->ext_host_addr, ip->protocol,
 279                   l_key.fib_index, l_key.port, s->ext_host_port);
 280     }
 281   kv.value = s - tsm->sessions;
 282   if (clib_bihash_add_or_overwrite_stale_16_8 (&tsm->in2out_ed, &kv,
 283                                                nat44_i2o_ed_is_idle_session_cb,
 284                                                &ctx))
 285     nat_elog_notice ("in2out-ed key add failed");
 286
 287   snat_ipfix_logging_nat44_ses_create (thread_index,
 288                                        s->in2out.addr.as_u32,
 289                                        s->out2in.addr.as_u32,
 290                                        s->in2out.protocol,
 291                                        s->in2out.port,
 292                                        s->out2in.port, s->in2out.fib_index);
 293
 294   nat_syslog_nat44_sadd (s->user_index, s->in2out.fib_index,
 295                          &s->in2out.addr, s->in2out.port,
 296                          &s->ext_host_nat_addr, s->ext_host_nat_port,
 297                          &s->out2in.addr, s->out2in.port,
 298                          &s->ext_host_addr, s->ext_host_port,
 299                          s->in2out.protocol, is_twice_nat_session (s));
 300
 301   nat_ha_sadd (&s->in2out.addr, s->in2out.port, &s->out2in.addr,
 302                s->out2in.port, &s->ext_host_addr, s->ext_host_port,
 303                &s->ext_host_nat_addr, s->ext_host_nat_port,
 304                s->in2out.protocol, s->in2out.fib_index, s->flags,
 305                thread_index, 0);
 306
 307   return s;
 308 }
 309
 310 static int
 311 next_src_nat (snat_main_t * sm, ip4_header_t * ip, u8 proto, u16 src_port,
 312               u16 dst_port, u32 thread_index, u32 rx_fib_index)
 313 {
 314   clib_bihash_kv_16_8_t kv, value;
 315   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 316
 317   make_ed_kv (&kv, &ip->src_address, &ip->dst_address, proto,
 318               rx_fib_index, src_port, dst_port);
 319   if (!clib_bihash_search_16_8 (&tsm->in2out_ed, &kv, &value))
 320     return 1;
 321
 322   return 0;
 323 }
 324
 325 static void
 326 create_bypass_for_fwd (snat_main_t * sm, ip4_header_t * ip, u32 rx_fib_index,
 327                        u32 thread_index)
 328 {
 329   nat_ed_ses_key_t key;
 330   clib_bihash_kv_16_8_t kv, value;
 331   udp_header_t *udp;
 332   snat_user_t *u;
 333   snat_session_t *s = 0;
 334   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 335   f64 now = vlib_time_now (sm->vlib_main);
 336
 337   if (ip->protocol == IP_PROTOCOL_ICMP)
 338     {
 339       if (get_icmp_o2i_ed_key (ip, &key))
 340         return;
 341     }
 342   else if (ip->protocol == IP_PROTOCOL_UDP || ip->protocol == IP_PROTOCOL_TCP)
 343     {
 344       udp = ip4_next_header (ip);
 345       key.r_addr = ip->src_address;
 346       key.l_addr = ip->dst_address;
 347       key.proto = ip->protocol;
 348       key.l_port = udp->dst_port;
 349       key.r_port = udp->src_port;
 350     }
 351   else
 352     {
 353       key.r_addr = ip->src_address;
 354       key.l_addr = ip->dst_address;
 355       key.proto = ip->protocol;
 356       key.l_port = key.r_port = 0;
 357     }
 358   key.fib_index = 0;
 359   kv.key[0] = key.as_u64[0];
 360   kv.key[1] = key.as_u64[1];
 361
 362   if (!clib_bihash_search_16_8 (&tsm->in2out_ed, &kv, &value))
 363     {
 364       s = pool_elt_at_index (tsm->sessions, value.value);
 365     }
 366   else
 367     {
 368       u32 proto;
 369
 370       if (PREDICT_FALSE (maximum_sessions_exceeded (sm, thread_index)))
 371         return;
 372
 373       u = nat_user_get_or_create (sm, &ip->dst_address, sm->inside_fib_index,
 374                                   thread_index);
 375       if (!u)
 376         {
 377           nat_elog_warn ("create NAT user failed");
 378           return;
 379         }
 380
 381       s = nat_ed_session_alloc (sm, u, thread_index, now);
 382       if (!s)
 383         {
 384           nat44_delete_user_with_no_session (sm, u, thread_index);
 385           nat_elog_warn ("create NAT session failed");
 386           return;
 387         }
 388
 389       proto = ip_proto_to_snat_proto (key.proto);
 390
 391       s->ext_host_addr = key.r_addr;
 392       s->ext_host_port = key.r_port;
 393       s->flags |= SNAT_SESSION_FLAG_FWD_BYPASS;
 394       s->out2in.addr = key.l_addr;
 395       s->out2in.port = key.l_port;
 396       s->out2in.protocol = proto;
 397       if (proto == ~0)
 398         {
 399           s->flags |= SNAT_SESSION_FLAG_UNKNOWN_PROTO;
 400           s->out2in.port = ip->protocol;
 401         }
 402       s->out2in.fib_index = 0;
 403       s->in2out = s->out2in;
 404       user_session_increment (sm, u, 0);
 405
 406       kv.value = s - tsm->sessions;
 407       if (clib_bihash_add_del_16_8 (&tsm->in2out_ed, &kv, 1))
 408         nat_elog_notice ("in2out_ed key add failed");
 409     }
 410
 411   if (ip->protocol == IP_PROTOCOL_TCP)
 412     {
 413       tcp_header_t *tcp = ip4_next_header (ip);
 414       if (nat44_set_tcp_session_state_o2i (sm, s, tcp, thread_index))
 415         return;
 416     }
 417
 418   /* Accounting */
 419   nat44_session_update_counters (s, now, 0, thread_index);
 420   /* Per-user LRU list maintenance */
 421   nat44_session_update_lru (sm, s, thread_index);
 422 }
 423
 424 static inline void
 425 create_bypass_for_fwd_worker (snat_main_t * sm, ip4_header_t * ip,
 426                               u32 rx_fib_index)
 427 {
 428   ip4_header_t ip_wkr = {
 429     .src_address = ip->dst_address,
 430   };
 431   u32 thread_index = sm->worker_in2out_cb (&ip_wkr, rx_fib_index, 0);
 432
 433   create_bypass_for_fwd (sm, ip, rx_fib_index, thread_index);
 434 }
 435
 436 #ifndef CLIB_MARCH_VARIANT
 437 u32
 438 icmp_match_out2in_ed (snat_main_t * sm, vlib_node_runtime_t * node,
 439                       u32 thread_index, vlib_buffer_t * b, ip4_header_t * ip,
 440                       u8 * p_proto, snat_session_key_t * p_value,
 441                       u8 * p_dont_translate, void *d, void *e)
 442 {
 443   u32 next = ~0, sw_if_index, rx_fib_index;
 444   icmp46_header_t *icmp;
 445   nat_ed_ses_key_t key;
 446   clib_bihash_kv_16_8_t kv, value;
 447   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 448   snat_session_t *s = 0;
 449   u8 dont_translate = 0, is_addr_only, identity_nat;
 450   snat_session_key_t e_key, l_key;
 451
 452   icmp = (icmp46_header_t *) ip4_next_header (ip);
 453   sw_if_index = vnet_buffer (b)->sw_if_index[VLIB_RX];
 454   rx_fib_index = ip4_fib_table_get_index_for_sw_if_index (sw_if_index);
 455
 456   if (get_icmp_o2i_ed_key (ip, &key))
 457     {
 458       b->error = node->errors[NAT_OUT2IN_ED_ERROR_UNSUPPORTED_PROTOCOL];
 459       next = NAT_NEXT_DROP;
 460       goto out;
 461     }
 462   key.fib_index = rx_fib_index;
 463   kv.key[0] = key.as_u64[0];
 464   kv.key[1] = key.as_u64[1];
 465
 466   if (clib_bihash_search_16_8 (&tsm->out2in_ed, &kv, &value))
 467     {
 468       /* Try to match static mapping */
 469       e_key.addr = ip->dst_address;
 470       e_key.port = key.l_port;
 471       e_key.protocol = ip_proto_to_snat_proto (key.proto);
 472       e_key.fib_index = rx_fib_index;
 473       if (snat_static_mapping_match
 474           (sm, e_key, &l_key, 1, &is_addr_only, 0, 0, 0, &identity_nat))
 475         {
 476           if (!sm->forwarding_enabled)
 477             {
 478               /* Don't NAT packet aimed at the intfc address */
 479               if (PREDICT_FALSE (is_interface_addr (sm, node, sw_if_index,
 480                                                     ip->dst_address.as_u32)))
 481                 {
 482                   dont_translate = 1;
 483                   goto out;
 484                 }
 485               b->error = node->errors[NAT_OUT2IN_ED_ERROR_NO_TRANSLATION];
 486               next = NAT_NEXT_DROP;
 487               goto out;
 488             }
 489           else
 490             {
 491               dont_translate = 1;
 492               if (next_src_nat (sm, ip, key.proto, key.l_port, key.r_port,
 493                                 thread_index, rx_fib_index))
 494                 {
 495                   next = NAT_NEXT_IN2OUT_ED_FAST_PATH;
 496                   goto out;
 497                 }
 498               if (sm->num_workers > 1)
 499                 create_bypass_for_fwd_worker (sm, ip, rx_fib_index);
 500               else
 501                 create_bypass_for_fwd (sm, ip, rx_fib_index, thread_index);
 502               goto out;
 503             }
 504         }
 505
 506       if (PREDICT_FALSE (icmp->type != ICMP4_echo_reply &&
 507                          (icmp->type != ICMP4_echo_request || !is_addr_only)))
 508         {
 509           b->error = node->errors[NAT_OUT2IN_ED_ERROR_BAD_ICMP_TYPE];
 510           next = NAT_NEXT_DROP;
 511           goto out;
 512         }
 513
 514       if (PREDICT_FALSE (identity_nat))
 515         {
 516           dont_translate = 1;
 517           goto out;
 518         }
 519
 520       /* Create session initiated by host from external network */
 521       s = create_session_for_static_mapping_ed (sm, b, l_key, e_key, node,
 522                                                 thread_index, 0, 0,
 523                                                 vlib_time_now
 524                                                 (sm->vlib_main));
 525
 526       if (!s)
 527         {
 528           next = NAT_NEXT_DROP;
 529           goto out;
 530         }
 531     }
 532   else
 533     {
 534       if (PREDICT_FALSE (icmp->type != ICMP4_echo_reply &&
 535                          icmp->type != ICMP4_echo_request &&
 536                          !icmp_is_error_message (icmp)))
 537         {
 538           b->error = node->errors[NAT_OUT2IN_ED_ERROR_BAD_ICMP_TYPE];
 539           next = NAT_NEXT_DROP;
 540           goto out;
 541         }
 542
 543       s = pool_elt_at_index (tsm->sessions, value.value);
 544     }
 545
 546   *p_proto = ip_proto_to_snat_proto (key.proto);
 547 out:
 548   if (s)
 549     *p_value = s->in2out;
 550   *p_dont_translate = dont_translate;
 551   if (d)
 552     *(snat_session_t **) d = s;
 553   return next;
 554 }
 555 #endif
 556
 557 static snat_session_t *
 558 nat44_ed_out2in_unknown_proto (snat_main_t * sm,
 559                                vlib_buffer_t * b,
 560                                ip4_header_t * ip,
 561                                u32 rx_fib_index,
 562                                u32 thread_index,
 563                                f64 now,
 564                                vlib_main_t * vm, vlib_node_runtime_t * node)
 565 {
 566   clib_bihash_kv_8_8_t kv, value;
 567   clib_bihash_kv_16_8_t s_kv, s_value;
 568   snat_static_mapping_t *m;
 569   u32 old_addr, new_addr;
 570   ip_csum_t sum;
 571   snat_session_t *s;
 572   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 573   snat_user_t *u;
 574
 575   old_addr = ip->dst_address.as_u32;
 576
 577   make_ed_kv (&s_kv, &ip->dst_address, &ip->src_address, ip->protocol,
 578               rx_fib_index, 0, 0);
 579
 580   if (!clib_bihash_search_16_8 (&tsm->out2in_ed, &s_kv, &s_value))
 581     {
 582       s = pool_elt_at_index (tsm->sessions, s_value.value);
 583       new_addr = ip->dst_address.as_u32 = s->in2out.addr.as_u32;
 584     }
 585   else
 586     {
 587       if (PREDICT_FALSE (maximum_sessions_exceeded (sm, thread_index)))
 588         {
 589           b->error = node->errors[NAT_OUT2IN_ED_ERROR_MAX_SESSIONS_EXCEEDED];
 590           nat_elog_notice ("maximum sessions exceeded");
 591           return 0;
 592         }
 593
 594       make_sm_kv (&kv, &ip->dst_address, 0, 0, 0);
 595       if (clib_bihash_search_8_8
 596           (&sm->static_mapping_by_external, &kv, &value))
 597         {
 598           b->error = node->errors[NAT_OUT2IN_ED_ERROR_NO_TRANSLATION];
 599           return 0;
 600         }
 601
 602       m = pool_elt_at_index (sm->static_mappings, value.value);
 603
 604       new_addr = ip->dst_address.as_u32 = m->local_addr.as_u32;
 605
 606       u = nat_user_get_or_create (sm, &m->local_addr, m->fib_index,
 607                                   thread_index);
 608       if (!u)
 609         {
 610           nat_elog_warn ("create NAT user failed");
 611           return 0;
 612         }
 613
 614       /* Create a new session */
 615       s = nat_ed_session_alloc (sm, u, thread_index, now);
 616       if (!s)
 617         {
 618           nat44_delete_user_with_no_session (sm, u, thread_index);
 619           nat_elog_warn ("create NAT session failed");
 620           return 0;
 621         }
 622
 623       s->ext_host_addr.as_u32 = ip->src_address.as_u32;
 624       s->flags |= SNAT_SESSION_FLAG_UNKNOWN_PROTO;
 625       s->flags |= SNAT_SESSION_FLAG_STATIC_MAPPING;
 626       s->flags |= SNAT_SESSION_FLAG_ENDPOINT_DEPENDENT;
 627       s->out2in.addr.as_u32 = old_addr;
 628       s->out2in.fib_index = rx_fib_index;
 629       s->in2out.addr.as_u32 = new_addr;
 630       s->in2out.fib_index = m->fib_index;
 631       s->in2out.port = s->out2in.port = ip->protocol;
 632       user_session_increment (sm, u, 1);
 633
 634       /* Add to lookup tables */
 635       s_kv.value = s - tsm->sessions;
 636       if (clib_bihash_add_del_16_8 (&tsm->out2in_ed, &s_kv, 1))
 637         nat_elog_notice ("out2in key add failed");
 638
 639       make_ed_kv (&s_kv, &ip->dst_address, &ip->src_address, ip->protocol,
 640                   m->fib_index, 0, 0);
 641       s_kv.value = s - tsm->sessions;
 642       if (clib_bihash_add_del_16_8 (&tsm->in2out_ed, &s_kv, 1))
 643         nat_elog_notice ("in2out key add failed");
 644     }
 645
 646   /* Update IP checksum */
 647   sum = ip->checksum;
 648   sum = ip_csum_update (sum, old_addr, new_addr, ip4_header_t, dst_address);
 649   ip->checksum = ip_csum_fold (sum);
 650
 651   vnet_buffer (b)->sw_if_index[VLIB_TX] = s->in2out.fib_index;
 652
 653   /* Accounting */
 654   nat44_session_update_counters (s, now, vlib_buffer_length_in_chain (vm, b),
 655                                  thread_index);
 656   /* Per-user LRU list maintenance */
 657   nat44_session_update_lru (sm, s, thread_index);
 658
 659   return s;
 660 }
 661
 662 static inline uword
 663 nat44_ed_out2in_node_fn_inline (vlib_main_t * vm,
 664                                 vlib_node_runtime_t * node,
 665                                 vlib_frame_t * frame, int is_slow_path)
 666 {
 667   u32 n_left_from, *from, *to_next, pkts_processed = 0, stats_node_index;
 668   nat_next_t next_index;
 669   snat_main_t *sm = &snat_main;
 670   f64 now = vlib_time_now (vm);
 671   u32 thread_index = vm->thread_index;
 672   snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
 673   u32 tcp_packets = 0, udp_packets = 0, icmp_packets = 0, other_packets =
 674     0, fragments = 0;
 675
 676   stats_node_index = is_slow_path ? sm->ed_out2in_slowpath_node_index :
 677     sm->ed_out2in_node_index;
 678
 679   from = vlib_frame_vector_args (frame);
 680   n_left_from = frame->n_vectors;
 681   next_index = node->cached_next_index;
 682
 683   while (n_left_from > 0)
 684     {
 685       u32 n_left_to_next;
 686
 687       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
 688
 689       while (n_left_from >= 4 && n_left_to_next >= 2)
 690         {
 691           u32 bi0, bi1;
 692           vlib_buffer_t *b0, *b1;
 693           u32 next0, sw_if_index0, rx_fib_index0, proto0, old_addr0,
 694             new_addr0;
 695           u32 next1, sw_if_index1, rx_fib_index1, proto1, old_addr1,
 696             new_addr1;
 697           u16 old_port0, new_port0, old_port1, new_port1;
 698           ip4_header_t *ip0, *ip1;
 699           udp_header_t *udp0, *udp1;
 700           tcp_header_t *tcp0, *tcp1;
 701           icmp46_header_t *icmp0, *icmp1;
 702           snat_session_t *s0 = 0, *s1 = 0;
 703           clib_bihash_kv_16_8_t kv0, value0, kv1, value1;
 704           ip_csum_t sum0, sum1;
 705           snat_session_key_t e_key0, l_key0, e_key1, l_key1;
 706           lb_nat_type_t lb_nat0, lb_nat1;
 707           twice_nat_type_t twice_nat0, twice_nat1;
 708           u8 identity_nat0, identity_nat1;
 709
 710           /* Prefetch next iteration. */
 711           {
 712             vlib_buffer_t *p2, *p3;
 713
 714             p2 = vlib_get_buffer (vm, from[2]);
 715             p3 = vlib_get_buffer (vm, from[3]);
 716
 717             vlib_prefetch_buffer_header (p2, LOAD);
 718             vlib_prefetch_buffer_header (p3, LOAD);
 719
 720             CLIB_PREFETCH (p2->data, CLIB_CACHE_LINE_BYTES, STORE);
 721             CLIB_PREFETCH (p3->data, CLIB_CACHE_LINE_BYTES, STORE);
 722           }
 723
 724           /* speculatively enqueue b0 and b1 to the current next frame */
 725           to_next[0] = bi0 = from[0];
 726           to_next[1] = bi1 = from[1];
 727           from += 2;
 728           to_next += 2;
 729           n_left_from -= 2;
 730           n_left_to_next -= 2;
 731
 732           b0 = vlib_get_buffer (vm, bi0);
 733           b1 = vlib_get_buffer (vm, bi1);
 734
 735           next0 = nat_buffer_opaque (b0)->arc_next;
 736           next1 = nat_buffer_opaque (b1)->arc_next;
 737
 738           vnet_buffer (b0)->snat.flags = 0;
 739           ip0 = vlib_buffer_get_current (b0);
 740
 741           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 742           rx_fib_index0 =
 743             fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4,
 744                                                  sw_if_index0);
 745
 746           if (PREDICT_FALSE (ip0->ttl == 1))
 747             {
 748               vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
 749               icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
 750                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
 751                                            0);
 752               next0 = NAT_NEXT_ICMP_ERROR;
 753               goto trace00;
 754             }
 755
 756           udp0 = ip4_next_header (ip0);
 757           tcp0 = (tcp_header_t *) udp0;
 758           icmp0 = (icmp46_header_t *) udp0;
 759           proto0 = ip_proto_to_snat_proto (ip0->protocol);
 760
 761           if (is_slow_path)
 762             {
 763               if (PREDICT_FALSE (proto0 == ~0))
 764                 {
 765                   s0 =
 766                     nat44_ed_out2in_unknown_proto (sm, b0, ip0, rx_fib_index0,
 767                                                    thread_index, now, vm,
 768                                                    node);
 769                   other_packets++;
 770                   if (!sm->forwarding_enabled)
 771                     {
 772                       if (!s0)
 773                         next0 = NAT_NEXT_DROP;
 774                       goto trace00;
 775                     }
 776                 }
 777
 778               if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
 779                 {
 780                   next0 = icmp_out2in_ed_slow_path
 781                     (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
 782                      next0, now, thread_index, &s0);
 783                   icmp_packets++;
 784                   goto trace00;
 785                 }
 786             }
 787           else
 788             {
 789               if (PREDICT_FALSE (proto0 == ~0))
 790                 {
 791                   next0 = NAT_NEXT_OUT2IN_ED_SLOW_PATH;
 792                   goto trace00;
 793                 }
 794
 795               if (ip4_is_fragment (ip0))
 796                 {
 797                   next0 = NAT_NEXT_OUT2IN_ED_REASS;
 798                   fragments++;
 799                   goto trace00;
 800                 }
 801
 802               if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
 803                 {
 804                   next0 = NAT_NEXT_OUT2IN_ED_SLOW_PATH;
 805                   goto trace00;
 806                 }
 807             }
 808
 809           make_ed_kv (&kv0, &ip0->dst_address, &ip0->src_address,
 810                       ip0->protocol, rx_fib_index0, udp0->dst_port,
 811                       udp0->src_port);
 812
 813           if (clib_bihash_search_16_8 (&tsm->out2in_ed, &kv0, &value0))
 814             {
 815               if (is_slow_path)
 816                 {
 817                   /* Try to match static mapping by external address and port,
 818                      destination address and port in packet */
 819                   e_key0.addr = ip0->dst_address;
 820                   e_key0.port = udp0->dst_port;
 821                   e_key0.protocol = proto0;
 822                   e_key0.fib_index = rx_fib_index0;
 823                   if (snat_static_mapping_match (sm, e_key0, &l_key0, 1, 0,
 824                                                  &twice_nat0, &lb_nat0,
 825                                                  &ip0->src_address,
 826                                                  &identity_nat0))
 827                     {
 828                       /*
 829                        * Send DHCP packets to the ipv4 stack, or we won't
 830                        * be able to use dhcp client on the outside interface
 831                        */
 832                       if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_UDP
 833                                          && (udp0->dst_port ==
 834                                              clib_host_to_net_u16
 835                                              (UDP_DST_PORT_dhcp_to_client))))
 836                         {
 837                           goto trace00;
 838                         }
 839
 840                       if (!sm->forwarding_enabled)
 841                         {
 842                           b0->error =
 843                             node->errors[NAT_OUT2IN_ED_ERROR_NO_TRANSLATION];
 844                           next0 = NAT_NEXT_DROP;
 845                         }
 846                       else
 847                         {
 848                           if (next_src_nat (sm, ip0, ip0->protocol,
 849                                             udp0->src_port, udp0->dst_port,
 850                                             thread_index, rx_fib_index0))
 851                             {
 852                               next0 = NAT_NEXT_IN2OUT_ED_FAST_PATH;
 853                               goto trace00;
 854                             }
 855                           if (sm->num_workers > 1)
 856                             create_bypass_for_fwd_worker (sm, ip0,
 857                                                           rx_fib_index0);
 858                           else
 859                             create_bypass_for_fwd (sm, ip0, rx_fib_index0,
 860                                                    thread_index);
 861                         }
 862                       goto trace00;
 863                     }
 864
 865                   if (PREDICT_FALSE (identity_nat0))
 866                     goto trace00;
 867
 868                   if ((proto0 == SNAT_PROTOCOL_TCP) && !tcp_is_init (tcp0))
 869                     {
 870                       b0->error = node->errors[NAT_OUT2IN_ED_ERROR_NON_SYN];
 871                       next0 = NAT_NEXT_DROP;
 872                       goto trace00;
 873                     }
 874
 875                   /* Create session initiated by host from external network */
 876                   s0 = create_session_for_static_mapping_ed (sm, b0, l_key0,
 877                                                              e_key0, node,
 878                                                              thread_index,
 879                                                              twice_nat0,
 880                                                              lb_nat0, now);
 881
 882                   if (!s0)
 883                     {
 884                       next0 = NAT_NEXT_DROP;
 885                       goto trace00;
 886                     }
 887                 }
 888               else
 889                 {
 890                   next0 = NAT_NEXT_OUT2IN_ED_SLOW_PATH;
 891                   goto trace00;
 892                 }
 893             }
 894           else
 895             {
 896               s0 = pool_elt_at_index (tsm->sessions, value0.value);
 897             }
 898
 899           old_addr0 = ip0->dst_address.as_u32;
 900           new_addr0 = ip0->dst_address.as_u32 = s0->in2out.addr.as_u32;
 901           vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->in2out.fib_index;
 902
 903           sum0 = ip0->checksum;
 904           sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
 905                                  dst_address);
 906           if (PREDICT_FALSE (is_twice_nat_session (s0)))
 907             sum0 = ip_csum_update (sum0, ip0->src_address.as_u32,
 908                                    s0->ext_host_nat_addr.as_u32, ip4_header_t,
 909                                    src_address);
 910           ip0->checksum = ip_csum_fold (sum0);
 911
 912           old_port0 = udp0->dst_port;
 913           new_port0 = udp0->dst_port = s0->in2out.port;
 914
 915           if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
 916             {
 917               sum0 = tcp0->checksum;
 918               sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
 919                                      dst_address);
 920               sum0 = ip_csum_update (sum0, old_port0, new_port0, ip4_header_t,
 921                                      length);
 922               if (is_twice_nat_session (s0))
 923                 {
 924                   sum0 = ip_csum_update (sum0, ip0->src_address.as_u32,
 925                                          s0->ext_host_nat_addr.as_u32,
 926                                          ip4_header_t, dst_address);
 927                   sum0 = ip_csum_update (sum0, tcp0->src_port,
 928                                          s0->ext_host_nat_port, ip4_header_t,
 929                                          length);
 930                   tcp0->src_port = s0->ext_host_nat_port;
 931                   ip0->src_address.as_u32 = s0->ext_host_nat_addr.as_u32;
 932                 }
 933               tcp0->checksum = ip_csum_fold (sum0);
 934               tcp_packets++;
 935               if (nat44_set_tcp_session_state_o2i
 936                   (sm, s0, tcp0, thread_index))
 937                 goto trace00;
 938             }
 939           else if (udp0->checksum)
 940             {
 941               sum0 = udp0->checksum;
 942               sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
 943                                      dst_address);
 944               sum0 = ip_csum_update (sum0, old_port0, new_port0, ip4_header_t,
 945                                      length);
 946               if (PREDICT_FALSE (is_twice_nat_session (s0)))
 947                 {
 948                   sum0 = ip_csum_update (sum0, ip0->src_address.as_u32,
 949                                          s0->ext_host_nat_addr.as_u32,
 950                                          ip4_header_t, dst_address);
 951                   sum0 = ip_csum_update (sum0, udp0->src_port,
 952                                          s0->ext_host_nat_port, ip4_header_t,
 953                                          length);
 954                   udp0->src_port = s0->ext_host_nat_port;
 955                   ip0->src_address.as_u32 = s0->ext_host_nat_addr.as_u32;
 956                 }
 957               udp0->checksum = ip_csum_fold (sum0);
 958               udp_packets++;
 959             }
 960           else
 961             {
 962               if (PREDICT_FALSE (is_twice_nat_session (s0)))
 963                 {
 964                   udp0->src_port = s0->ext_host_nat_port;
 965                   ip0->src_address.as_u32 = s0->ext_host_nat_addr.as_u32;
 966                 }
 967               udp_packets++;
 968             }
 969
 970           /* Accounting */
 971           nat44_session_update_counters (s0, now,
 972                                          vlib_buffer_length_in_chain (vm, b0),
 973                                          thread_index);
 974           /* Per-user LRU list maintenance */
 975           nat44_session_update_lru (sm, s0, thread_index);
 976
 977         trace00:
 978           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
 979                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
 980             {
 981               nat44_ed_out2in_trace_t *t =
 982                 vlib_add_trace (vm, node, b0, sizeof (*t));
 983               t->is_slow_path = is_slow_path;
 984               t->sw_if_index = sw_if_index0;
 985               t->next_index = next0;
 986               t->session_index = ~0;
 987               if (s0)
 988                 t->session_index = s0 - tsm->sessions;
 989             }
 990
 991           pkts_processed += next0 == nat_buffer_opaque (b0)->arc_next;
 992
 993           vnet_buffer (b1)->snat.flags = 0;
 994           ip1 = vlib_buffer_get_current (b1);
 995
 996           sw_if_index1 = vnet_buffer (b1)->sw_if_index[VLIB_RX];
 997           rx_fib_index1 =
 998             fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4,
 999                                                  sw_if_index1);
1000
1001           if (PREDICT_FALSE (ip1->ttl == 1))
1002             {
1003               vnet_buffer (b1)->sw_if_index[VLIB_TX] = (u32) ~ 0;
1004               icmp4_error_set_vnet_buffer (b1, ICMP4_time_exceeded,
1005                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
1006                                            0);
1007               next1 = NAT_NEXT_ICMP_ERROR;
1008               goto trace01;
1009             }
1010
1011           udp1 = ip4_next_header (ip1);
1012           tcp1 = (tcp_header_t *) udp1;
1013           icmp1 = (icmp46_header_t *) udp1;
1014           proto1 = ip_proto_to_snat_proto (ip1->protocol);
1015
1016           if (is_slow_path)
1017             {
1018               if (PREDICT_FALSE (proto1 == ~0))
1019                 {
1020                   s1 =
1021                     nat44_ed_out2in_unknown_proto (sm, b1, ip1, rx_fib_index1,
1022                                                    thread_index, now, vm,
1023                                                    node);
1024                   other_packets++;
1025                   if (!sm->forwarding_enabled)
1026                     {
1027                       if (!s1)
1028                         next1 = NAT_NEXT_DROP;
1029                       goto trace01;
1030                     }
1031                 }
1032
1033               if (PREDICT_FALSE (proto1 == SNAT_PROTOCOL_ICMP))
1034                 {
1035                   next1 = icmp_out2in_ed_slow_path
1036                     (sm, b1, ip1, icmp1, sw_if_index1, rx_fib_index1, node,
1037                      next1, now, thread_index, &s1);
1038                   icmp_packets++;
1039                   goto trace01;
1040                 }
1041             }
1042           else
1043             {
1044               if (PREDICT_FALSE (proto1 == ~0))
1045                 {
1046                   next1 = NAT_NEXT_OUT2IN_ED_SLOW_PATH;
1047                   goto trace01;
1048                 }
1049
1050               if (ip4_is_fragment (ip1))
1051                 {
1052                   next1 = NAT_NEXT_OUT2IN_ED_REASS;
1053                   fragments++;
1054                   goto trace01;
1055                 }
1056
1057               if (PREDICT_FALSE (proto1 == SNAT_PROTOCOL_ICMP))
1058                 {
1059                   next1 = NAT_NEXT_OUT2IN_ED_SLOW_PATH;
1060                   goto trace01;
1061                 }
1062             }
1063
1064           make_ed_kv (&kv1, &ip1->dst_address, &ip1->src_address,
1065                       ip1->protocol, rx_fib_index1, udp1->dst_port,
1066                       udp1->src_port);
1067
1068           if (clib_bihash_search_16_8 (&tsm->out2in_ed, &kv1, &value1))
1069             {
1070               if (is_slow_path)
1071                 {
1072                   /* Try to match static mapping by external address and port,
1073                      destination address and port in packet */
1074                   e_key1.addr = ip1->dst_address;
1075                   e_key1.port = udp1->dst_port;
1076                   e_key1.protocol = proto1;
1077                   e_key1.fib_index = rx_fib_index1;
1078                   if (snat_static_mapping_match (sm, e_key1, &l_key1, 1, 0,
1079                                                  &twice_nat1, &lb_nat1,
1080                                                  &ip1->src_address,
1081                                                  &identity_nat1))
1082                     {
1083                       /*
1084                        * Send DHCP packets to the ipv4 stack, or we won't
1085                        * be able to use dhcp client on the outside interface
1086                        */
1087                       if (PREDICT_FALSE (proto1 == SNAT_PROTOCOL_UDP
1088                                          && (udp1->dst_port ==
1089                                              clib_host_to_net_u16
1090                                              (UDP_DST_PORT_dhcp_to_client))))
1091                         {
1092                           goto trace01;
1093                         }
1094
1095                       if (!sm->forwarding_enabled)
1096                         {
1097                           b1->error =
1098                             node->errors[NAT_OUT2IN_ED_ERROR_NO_TRANSLATION];
1099                           next1 = NAT_NEXT_DROP;
1100                         }
1101                       else
1102                         {
1103                           if (next_src_nat (sm, ip1, ip1->protocol,
1104                                             udp1->src_port, udp1->dst_port,
1105                                             thread_index, rx_fib_index1))
1106                             {
1107                               next1 = NAT_NEXT_IN2OUT_ED_FAST_PATH;
1108                               goto trace01;
1109                             }
1110                           if (sm->num_workers > 1)
1111                             create_bypass_for_fwd_worker (sm, ip1,
1112                                                           rx_fib_index1);
1113                           else
1114                             create_bypass_for_fwd (sm, ip1, rx_fib_index1,
1115                                                    thread_index);
1116                         }
1117                       goto trace01;
1118                     }
1119
1120                   if (PREDICT_FALSE (identity_nat1))
1121                     goto trace01;
1122
1123                   if ((proto1 == SNAT_PROTOCOL_TCP) && !tcp_is_init (tcp1))
1124                     {
1125                       b1->error = node->errors[NAT_OUT2IN_ED_ERROR_NON_SYN];
1126                       next1 = NAT_NEXT_DROP;
1127                       goto trace01;
1128                     }
1129
1130                   /* Create session initiated by host from external network */
1131                   s1 = create_session_for_static_mapping_ed (sm, b1, l_key1,
1132                                                              e_key1, node,
1133                                                              thread_index,
1134                                                              twice_nat1,
1135                                                              lb_nat1, now);
1136
1137                   if (!s1)
1138                     {
1139                       next1 = NAT_NEXT_DROP;
1140                       goto trace01;
1141                     }
1142                 }
1143               else
1144                 {
1145                   next1 = NAT_NEXT_OUT2IN_ED_SLOW_PATH;
1146                   goto trace01;
1147                 }
1148             }
1149           else
1150             {
1151               s1 = pool_elt_at_index (tsm->sessions, value1.value);
1152             }
1153
1154           old_addr1 = ip1->dst_address.as_u32;
1155           new_addr1 = ip1->dst_address.as_u32 = s1->in2out.addr.as_u32;
1156           vnet_buffer (b1)->sw_if_index[VLIB_TX] = s1->in2out.fib_index;
1157
1158           sum1 = ip1->checksum;
1159           sum1 = ip_csum_update (sum1, old_addr1, new_addr1, ip4_header_t,
1160                                  dst_address);
1161           if (PREDICT_FALSE (is_twice_nat_session (s1)))
1162             sum1 = ip_csum_update (sum1, ip1->src_address.as_u32,
1163                                    s1->ext_host_nat_addr.as_u32, ip4_header_t,
1164                                    src_address);
1165           ip1->checksum = ip_csum_fold (sum1);
1166
1167           old_port1 = udp1->dst_port;
1168           new_port1 = udp1->dst_port = s1->in2out.port;
1169
1170           if (PREDICT_TRUE (proto1 == SNAT_PROTOCOL_TCP))
1171             {
1172               sum1 = tcp1->checksum;
1173               sum1 = ip_csum_update (sum1, old_addr1, new_addr1, ip4_header_t,
1174                                      dst_address);
1175               sum1 = ip_csum_update (sum1, old_port1, new_port1, ip4_header_t,
1176                                      length);
1177               if (is_twice_nat_session (s1))
1178                 {
1179                   sum1 = ip_csum_update (sum1, ip1->src_address.as_u32,
1180                                          s1->ext_host_nat_addr.as_u32,
1181                                          ip4_header_t, dst_address);
1182                   sum1 = ip_csum_update (sum1, tcp1->src_port,
1183                                          s1->ext_host_nat_port, ip4_header_t,
1184                                          length);
1185                   tcp1->src_port = s1->ext_host_nat_port;
1186                   ip1->src_address.as_u32 = s1->ext_host_nat_addr.as_u32;
1187                 }
1188               tcp1->checksum = ip_csum_fold (sum1);
1189               tcp_packets++;
1190               if (nat44_set_tcp_session_state_o2i
1191                   (sm, s1, tcp1, thread_index))
1192                 goto trace01;
1193             }
1194           else if (udp1->checksum)
1195             {
1196               sum1 = udp1->checksum;
1197               sum1 = ip_csum_update (sum1, old_addr1, new_addr1, ip4_header_t,
1198                                      dst_address);
1199               sum1 = ip_csum_update (sum1, old_port1, new_port1, ip4_header_t,
1200                                      length);
1201               if (PREDICT_FALSE (is_twice_nat_session (s1)))
1202                 {
1203                   sum1 = ip_csum_update (sum1, ip1->src_address.as_u32,
1204                                          s1->ext_host_nat_addr.as_u32,
1205                                          ip4_header_t, dst_address);
1206                   sum1 = ip_csum_update (sum1, udp1->src_port,
1207                                          s1->ext_host_nat_port, ip4_header_t,
1208                                          length);
1209                   udp1->src_port = s1->ext_host_nat_port;
1210                   ip1->src_address.as_u32 = s1->ext_host_nat_addr.as_u32;
1211                 }
1212               udp1->checksum = ip_csum_fold (sum1);
1213               udp_packets++;
1214             }
1215           else
1216             {
1217               if (PREDICT_FALSE (is_twice_nat_session (s1)))
1218                 {
1219                   udp1->src_port = s1->ext_host_nat_port;
1220                   ip1->src_address.as_u32 = s1->ext_host_nat_addr.as_u32;
1221                 }
1222               udp_packets++;
1223             }
1224
1225           /* Accounting */
1226           nat44_session_update_counters (s1, now,
1227                                          vlib_buffer_length_in_chain (vm, b1),
1228                                          thread_index);
1229           /* Per-user LRU list maintenance */
1230           nat44_session_update_lru (sm, s1, thread_index);
1231
1232         trace01:
1233           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1234                              && (b1->flags & VLIB_BUFFER_IS_TRACED)))
1235             {
1236               nat44_ed_out2in_trace_t *t =
1237                 vlib_add_trace (vm, node, b1, sizeof (*t));
1238               t->is_slow_path = is_slow_path;
1239               t->sw_if_index = sw_if_index1;
1240               t->next_index = next1;
1241               t->session_index = ~0;
1242               if (s1)
1243                 t->session_index = s1 - tsm->sessions;
1244             }
1245
1246           pkts_processed += next1 == nat_buffer_opaque (b1)->arc_next;
1247
1248           /* verify speculative enqueues, maybe switch current next frame */
1249           vlib_validate_buffer_enqueue_x2 (vm, node, next_index,
1250                                            to_next, n_left_to_next,
1251                                            bi0, bi1, next0, next1);
1252         }
1253
1254       while (n_left_from > 0 && n_left_to_next > 0)
1255         {
1256           u32 bi0;
1257           vlib_buffer_t *b0;
1258           u32 next0, sw_if_index0, rx_fib_index0, proto0, old_addr0,
1259             new_addr0;
1260           u16 old_port0, new_port0;
1261           ip4_header_t *ip0;
1262           udp_header_t *udp0;
1263           tcp_header_t *tcp0;
1264           icmp46_header_t *icmp0;
1265           snat_session_t *s0 = 0;
1266           clib_bihash_kv_16_8_t kv0, value0;
1267           ip_csum_t sum0;
1268           snat_session_key_t e_key0, l_key0;
1269           lb_nat_type_t lb_nat0;
1270           twice_nat_type_t twice_nat0;
1271           u8 identity_nat0;
1272
1273           /* speculatively enqueue b0 to the current next frame */
1274           bi0 = from[0];
1275           to_next[0] = bi0;
1276           from += 1;
1277           to_next += 1;
1278           n_left_from -= 1;
1279           n_left_to_next -= 1;
1280
1281           b0 = vlib_get_buffer (vm, bi0);
1282           next0 = nat_buffer_opaque (b0)->arc_next;
1283
1284           vnet_buffer (b0)->snat.flags = 0;
1285           ip0 = vlib_buffer_get_current (b0);
1286
1287           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1288           rx_fib_index0 =
1289             fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4,
1290                                                  sw_if_index0);
1291
1292           if (PREDICT_FALSE (ip0->ttl == 1))
1293             {
1294               vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
1295               icmp4_error_set_vnet_buffer (b0, ICMP4_time_exceeded,
1296                                            ICMP4_time_exceeded_ttl_exceeded_in_transit,
1297                                            0);
1298               next0 = NAT_NEXT_ICMP_ERROR;
1299               goto trace0;
1300             }
1301
1302           udp0 = ip4_next_header (ip0);
1303           tcp0 = (tcp_header_t *) udp0;
1304           icmp0 = (icmp46_header_t *) udp0;
1305           proto0 = ip_proto_to_snat_proto (ip0->protocol);
1306
1307           if (is_slow_path)
1308             {
1309               if (PREDICT_FALSE (proto0 == ~0))
1310                 {
1311                   s0 =
1312                     nat44_ed_out2in_unknown_proto (sm, b0, ip0, rx_fib_index0,
1313                                                    thread_index, now, vm,
1314                                                    node);
1315                   other_packets++;
1316                   if (!sm->forwarding_enabled)
1317                     {
1318                       if (!s0)
1319                         next0 = NAT_NEXT_DROP;
1320                       goto trace0;
1321                     }
1322                 }
1323
1324               if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
1325                 {
1326                   next0 = icmp_out2in_ed_slow_path
1327                     (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
1328                      next0, now, thread_index, &s0);
1329                   icmp_packets++;
1330                   goto trace0;
1331                 }
1332             }
1333           else
1334             {
1335               if (PREDICT_FALSE (proto0 == ~0))
1336                 {
1337                   next0 = NAT_NEXT_OUT2IN_ED_SLOW_PATH;
1338                   goto trace0;
1339                 }
1340
1341               if (ip4_is_fragment (ip0))
1342                 {
1343                   next0 = NAT_NEXT_OUT2IN_ED_REASS;
1344                   fragments++;
1345                   goto trace0;
1346                 }
1347
1348               if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
1349                 {
1350                   next0 = NAT_NEXT_OUT2IN_ED_SLOW_PATH;
1351                   goto trace0;
1352                 }
1353             }
1354
1355           make_ed_kv (&kv0, &ip0->dst_address, &ip0->src_address,
1356                       ip0->protocol, rx_fib_index0, udp0->dst_port,
1357                       udp0->src_port);
1358
1359           if (clib_bihash_search_16_8 (&tsm->out2in_ed, &kv0, &value0))
1360             {
1361               if (is_slow_path)
1362                 {
1363                   /* Try to match static mapping by external address and port,
1364                      destination address and port in packet */
1365                   e_key0.addr = ip0->dst_address;
1366                   e_key0.port = udp0->dst_port;
1367                   e_key0.protocol = proto0;
1368                   e_key0.fib_index = rx_fib_index0;
1369                   if (snat_static_mapping_match (sm, e_key0, &l_key0, 1, 0,
1370                                                  &twice_nat0, &lb_nat0,
1371                                                  &ip0->src_address,
1372                                                  &identity_nat0))
1373                     {
1374                       /*
1375                        * Send DHCP packets to the ipv4 stack, or we won't
1376                        * be able to use dhcp client on the outside interface
1377                        */
1378                       if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_UDP
1379                                          && (udp0->dst_port ==
1380                                              clib_host_to_net_u16
1381                                              (UDP_DST_PORT_dhcp_to_client))))
1382                         {
1383                           goto trace0;
1384                         }
1385
1386                       if (!sm->forwarding_enabled)
1387                         {
1388                           b0->error =
1389                             node->errors[NAT_OUT2IN_ED_ERROR_NO_TRANSLATION];
1390                           next0 = NAT_NEXT_DROP;
1391                         }
1392                       else
1393                         {
1394                           if (next_src_nat (sm, ip0, ip0->protocol,
1395                                             udp0->src_port, udp0->dst_port,
1396                                             thread_index, rx_fib_index0))
1397                             {
1398                               next0 = NAT_NEXT_IN2OUT_ED_FAST_PATH;
1399                               goto trace0;
1400                             }
1401                           if (sm->num_workers > 1)
1402                             create_bypass_for_fwd_worker (sm, ip0,
1403                                                           rx_fib_index0);
1404                           else
1405                             create_bypass_for_fwd (sm, ip0, rx_fib_index0,
1406                                                    thread_index);
1407                         }
1408                       goto trace0;
1409                     }
1410
1411                   if (PREDICT_FALSE (identity_nat0))
1412                     goto trace0;
1413
1414                   if ((proto0 == SNAT_PROTOCOL_TCP) && !tcp_is_init (tcp0))
1415                     {
1416                       b0->error = node->errors[NAT_OUT2IN_ED_ERROR_NON_SYN];
1417                       next0 = NAT_NEXT_DROP;
1418                       goto trace0;
1419                     }
1420
1421                   /* Create session initiated by host from external network */
1422                   s0 = create_session_for_static_mapping_ed (sm, b0, l_key0,
1423                                                              e_key0, node,
1424                                                              thread_index,
1425                                                              twice_nat0,
1426                                                              lb_nat0, now);
1427
1428                   if (!s0)
1429                     {
1430                       next0 = NAT_NEXT_DROP;
1431                       goto trace0;
1432                     }
1433                 }
1434               else
1435                 {
1436                   next0 = NAT_NEXT_OUT2IN_ED_SLOW_PATH;
1437                   goto trace0;
1438                 }
1439             }
1440           else
1441             {
1442               s0 = pool_elt_at_index (tsm->sessions, value0.value);
1443             }
1444
1445           old_addr0 = ip0->dst_address.as_u32;
1446           new_addr0 = ip0->dst_address.as_u32 = s0->in2out.addr.as_u32;
1447           vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->in2out.fib_index;
1448
1449           sum0 = ip0->checksum;
1450           sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1451                                  dst_address);
1452           if (PREDICT_FALSE (is_twice_nat_session (s0)))
1453             sum0 = ip_csum_update (sum0, ip0->src_address.as_u32,
1454                                    s0->ext_host_nat_addr.as_u32, ip4_header_t,
1455                                    src_address);
1456           ip0->checksum = ip_csum_fold (sum0);
1457
1458           old_port0 = udp0->dst_port;
1459           new_port0 = udp0->dst_port = s0->in2out.port;
1460
1461           if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
1462             {
1463               sum0 = tcp0->checksum;
1464               sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1465                                      dst_address);
1466               sum0 = ip_csum_update (sum0, old_port0, new_port0, ip4_header_t,
1467                                      length);
1468               if (is_twice_nat_session (s0))
1469                 {
1470                   sum0 = ip_csum_update (sum0, ip0->src_address.as_u32,
1471                                          s0->ext_host_nat_addr.as_u32,
1472                                          ip4_header_t, dst_address);
1473                   sum0 = ip_csum_update (sum0, tcp0->src_port,
1474                                          s0->ext_host_nat_port, ip4_header_t,
1475                                          length);
1476                   tcp0->src_port = s0->ext_host_nat_port;
1477                   ip0->src_address.as_u32 = s0->ext_host_nat_addr.as_u32;
1478                 }
1479               tcp0->checksum = ip_csum_fold (sum0);
1480               tcp_packets++;
1481               if (nat44_set_tcp_session_state_o2i
1482                   (sm, s0, tcp0, thread_index))
1483                 goto trace0;
1484             }
1485           else if (udp0->checksum)
1486             {
1487               sum0 = udp0->checksum;
1488               sum0 = ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1489                                      dst_address);
1490               sum0 = ip_csum_update (sum0, old_port0, new_port0, ip4_header_t,
1491                                      length);
1492               if (PREDICT_FALSE (is_twice_nat_session (s0)))
1493                 {
1494                   sum0 = ip_csum_update (sum0, ip0->src_address.as_u32,
1495                                          s0->ext_host_nat_addr.as_u32,
1496                                          ip4_header_t, dst_address);
1497                   sum0 = ip_csum_update (sum0, udp0->src_port,
1498                                          s0->ext_host_nat_port, ip4_header_t,
1499                                          length);
1500                   udp0->src_port = s0->ext_host_nat_port;
1501                   ip0->src_address.as_u32 = s0->ext_host_nat_addr.as_u32;
1502                 }
1503               udp0->checksum = ip_csum_fold (sum0);
1504               udp_packets++;
1505             }
1506           else
1507             {
1508               if (PREDICT_FALSE (is_twice_nat_session (s0)))
1509                 {
1510                   udp0->src_port = s0->ext_host_nat_port;
1511                   ip0->src_address.as_u32 = s0->ext_host_nat_addr.as_u32;
1512                 }
1513               udp_packets++;
1514             }
1515
1516           /* Accounting */
1517           nat44_session_update_counters (s0, now,
1518                                          vlib_buffer_length_in_chain (vm, b0),
1519                                          thread_index);
1520           /* Per-user LRU list maintenance */
1521           nat44_session_update_lru (sm, s0, thread_index);
1522
1523         trace0:
1524           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1525                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1526             {
1527               nat44_ed_out2in_trace_t *t =
1528                 vlib_add_trace (vm, node, b0, sizeof (*t));
1529               t->is_slow_path = is_slow_path;
1530               t->sw_if_index = sw_if_index0;
1531               t->next_index = next0;
1532               t->session_index = ~0;
1533               if (s0)
1534                 t->session_index = s0 - tsm->sessions;
1535             }
1536
1537           pkts_processed += next0 == nat_buffer_opaque (b0)->arc_next;
1538           /* verify speculative enqueue, maybe switch current next frame */
1539           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
1540                                            to_next, n_left_to_next,
1541                                            bi0, next0);
1542         }
1543
1544       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
1545     }
1546
1547   vlib_node_increment_counter (vm, stats_node_index,
1548                                NAT_OUT2IN_ED_ERROR_OUT2IN_PACKETS,
1549                                pkts_processed);
1550   vlib_node_increment_counter (vm, stats_node_index,
1551                                NAT_OUT2IN_ED_ERROR_TCP_PACKETS, tcp_packets);
1552   vlib_node_increment_counter (vm, stats_node_index,
1553                                NAT_OUT2IN_ED_ERROR_UDP_PACKETS, udp_packets);
1554   vlib_node_increment_counter (vm, stats_node_index,
1555                                NAT_OUT2IN_ED_ERROR_ICMP_PACKETS,
1556                                icmp_packets);
1557   vlib_node_increment_counter (vm, stats_node_index,
1558                                NAT_OUT2IN_ED_ERROR_OTHER_PACKETS,
1559                                other_packets);
1560   vlib_node_increment_counter (vm, stats_node_index,
1561                                NAT_OUT2IN_ED_ERROR_FRAGMENTS, fragments);
1562   return frame->n_vectors;
1563 }
1564
1565 static inline uword
1566 nat44_ed_out2in_reass_node_fn_inline (vlib_main_t * vm,
1567                                       vlib_node_runtime_t * node,
1568                                       vlib_frame_t * frame)
1569 {
1570   u32 n_left_from, *from, *to_next;
1571   nat_next_t next_index;
1572   u32 pkts_processed = 0;
1573   snat_main_t *sm = &snat_main;
1574   f64 now = vlib_time_now (vm);
1575   u32 thread_index = vm->thread_index;
1576   snat_main_per_thread_data_t *per_thread_data =
1577     &sm->per_thread_data[thread_index];
1578   u32 *fragments_to_drop = 0;
1579   u32 *fragments_to_loopback = 0;
1580
1581   from = vlib_frame_vector_args (frame);
1582   n_left_from = frame->n_vectors;
1583   next_index = node->cached_next_index;
1584
1585   while (n_left_from > 0)
1586     {
1587       u32 n_left_to_next;
1588
1589       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
1590
1591       while (n_left_from > 0 && n_left_to_next > 0)
1592         {
1593           u32 bi0, sw_if_index0, proto0, rx_fib_index0, new_addr0, old_addr0;
1594           vlib_buffer_t *b0;
1595           u32 next0;
1596           u8 cached0 = 0;
1597           ip4_header_t *ip0;
1598           nat_reass_ip4_t *reass0;
1599           udp_header_t *udp0;
1600           tcp_header_t *tcp0;
1601           icmp46_header_t *icmp0;
1602           clib_bihash_kv_16_8_t kv0, value0;
1603           snat_session_t *s0 = 0;
1604           u16 old_port0, new_port0;
1605           ip_csum_t sum0;
1606           snat_session_key_t e_key0, l_key0;
1607           lb_nat_type_t lb0;
1608           twice_nat_type_t twice_nat0;
1609           u8 identity_nat0;
1610
1611           /* speculatively enqueue b0 to the current next frame */
1612           bi0 = from[0];
1613           to_next[0] = bi0;
1614           from += 1;
1615           to_next += 1;
1616           n_left_from -= 1;
1617           n_left_to_next -= 1;
1618
1619           b0 = vlib_get_buffer (vm, bi0);
1620           next0 = nat_buffer_opaque (b0)->arc_next;
1621
1622           sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
1623           rx_fib_index0 =
1624             fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4,
1625                                                  sw_if_index0);
1626
1627           if (PREDICT_FALSE (nat_reass_is_drop_frag (0)))
1628             {
1629               next0 = NAT_NEXT_DROP;
1630               b0->error = node->errors[NAT_OUT2IN_ED_ERROR_DROP_FRAGMENT];
1631               goto trace0;
1632             }
1633
1634           ip0 = (ip4_header_t *) vlib_buffer_get_current (b0);
1635           udp0 = ip4_next_header (ip0);
1636           tcp0 = (tcp_header_t *) udp0;
1637           icmp0 = (icmp46_header_t *) udp0;
1638           proto0 = ip_proto_to_snat_proto (ip0->protocol);
1639
1640           reass0 = nat_ip4_reass_find_or_create (ip0->src_address,
1641                                                  ip0->dst_address,
1642                                                  ip0->fragment_id,
1643                                                  ip0->protocol,
1644                                                  1, &fragments_to_drop);
1645
1646           if (PREDICT_FALSE (!reass0))
1647             {
1648               next0 = NAT_NEXT_DROP;
1649               b0->error = node->errors[NAT_OUT2IN_ED_ERROR_MAX_REASS];
1650               nat_elog_notice ("maximum reassemblies exceeded");
1651               goto trace0;
1652             }
1653
1654           if (PREDICT_FALSE (ip4_is_first_fragment (ip0)))
1655             {
1656               if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
1657                 {
1658                   next0 = icmp_out2in_ed_slow_path
1659                     (sm, b0, ip0, icmp0, sw_if_index0, rx_fib_index0, node,
1660                      next0, now, thread_index, &s0);
1661
1662                   if (PREDICT_TRUE (next0 != NAT_NEXT_DROP))
1663                     {
1664                       if (s0)
1665                         reass0->sess_index = s0 - per_thread_data->sessions;
1666                       else
1667                         reass0->flags |= NAT_REASS_FLAG_ED_DONT_TRANSLATE;
1668                       reass0->thread_index = thread_index;
1669                       nat_ip4_reass_get_frags (reass0,
1670                                                &fragments_to_loopback);
1671                     }
1672
1673                   goto trace0;
1674                 }
1675
1676               make_ed_kv (&kv0, &ip0->dst_address, &ip0->src_address,
1677                           ip0->protocol, rx_fib_index0, udp0->dst_port,
1678                           udp0->src_port);
1679
1680               if (clib_bihash_search_16_8
1681                   (&per_thread_data->out2in_ed, &kv0, &value0))
1682                 {
1683                   /* Try to match static mapping by external address and port,
1684                      destination address and port in packet */
1685                   e_key0.addr = ip0->dst_address;
1686                   e_key0.port = udp0->dst_port;
1687                   e_key0.protocol = proto0;
1688                   e_key0.fib_index = rx_fib_index0;
1689                   if (snat_static_mapping_match (sm, e_key0, &l_key0, 1, 0,
1690                                                  &twice_nat0, &lb0, 0,
1691                                                  &identity_nat0))
1692                     {
1693                       /*
1694                        * Send DHCP packets to the ipv4 stack, or we won't
1695                        * be able to use dhcp client on the outside interface
1696                        */
1697                       if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_UDP
1698                                          && (udp0->dst_port
1699                                              ==
1700                                              clib_host_to_net_u16
1701                                              (UDP_DST_PORT_dhcp_to_client))))
1702                         {
1703                           goto trace0;
1704                         }
1705
1706                       if (!sm->forwarding_enabled)
1707                         {
1708                           b0->error =
1709                             node->errors[NAT_OUT2IN_ED_ERROR_NO_TRANSLATION];
1710                           next0 = NAT_NEXT_DROP;
1711                         }
1712                       else
1713                         {
1714                           if (next_src_nat (sm, ip0, ip0->protocol,
1715                                             udp0->src_port, udp0->dst_port,
1716                                             thread_index, rx_fib_index0))
1717                             {
1718                               next0 = NAT_NEXT_IN2OUT_ED_FAST_PATH;
1719                               goto trace0;
1720                             }
1721                           if (sm->num_workers > 1)
1722                             create_bypass_for_fwd_worker (sm, ip0,
1723                                                           rx_fib_index0);
1724                           else
1725                             create_bypass_for_fwd (sm, ip0, rx_fib_index0,
1726                                                    thread_index);
1727                           reass0->flags |= NAT_REASS_FLAG_ED_DONT_TRANSLATE;
1728                           nat_ip4_reass_get_frags (reass0,
1729                                                    &fragments_to_loopback);
1730                         }
1731                       goto trace0;
1732                     }
1733
1734                   if (PREDICT_FALSE (identity_nat0))
1735                     {
1736                       reass0->flags |= NAT_REASS_FLAG_ED_DONT_TRANSLATE;
1737                       goto trace0;
1738                     }
1739
1740                   if ((proto0 == SNAT_PROTOCOL_TCP) && !tcp_is_init (tcp0))
1741                     {
1742                       b0->error = node->errors[NAT_OUT2IN_ED_ERROR_NON_SYN];
1743                       next0 = NAT_NEXT_DROP;
1744                       goto trace0;
1745                     }
1746
1747                   /* Create session initiated by host from external network */
1748                   s0 = create_session_for_static_mapping_ed (sm, b0, l_key0,
1749                                                              e_key0, node,
1750                                                              thread_index,
1751                                                              twice_nat0, lb0,
1752                                                              now);
1753                   if (!s0)
1754                     {
1755                       b0->error =
1756                         node->errors[NAT_OUT2IN_ED_ERROR_NO_TRANSLATION];
1757                       next0 = NAT_NEXT_DROP;
1758                       goto trace0;
1759                     }
1760                   reass0->sess_index = s0 - per_thread_data->sessions;
1761                   reass0->thread_index = thread_index;
1762                 }
1763               else
1764                 {
1765                   s0 = pool_elt_at_index (per_thread_data->sessions,
1766                                           value0.value);
1767                   reass0->sess_index = value0.value;
1768                 }
1769               nat_ip4_reass_get_frags (reass0, &fragments_to_loopback);
1770             }
1771           else
1772             {
1773               if (reass0->flags & NAT_REASS_FLAG_ED_DONT_TRANSLATE)
1774                 goto trace0;
1775               if (PREDICT_FALSE (reass0->sess_index == (u32) ~ 0))
1776                 {
1777                   if (nat_ip4_reass_add_fragment
1778                       (thread_index, reass0, bi0, &fragments_to_drop))
1779                     {
1780                       b0->error = node->errors[NAT_OUT2IN_ED_ERROR_MAX_FRAG];
1781                       nat_elog_notice
1782                         ("maximum fragments per reassembly exceeded");
1783                       next0 = NAT_NEXT_DROP;
1784                       goto trace0;
1785                     }
1786                   cached0 = 1;
1787                   goto trace0;
1788                 }
1789               s0 = pool_elt_at_index (per_thread_data->sessions,
1790                                       reass0->sess_index);
1791             }
1792
1793           old_addr0 = ip0->dst_address.as_u32;
1794           ip0->dst_address = s0->in2out.addr;
1795           new_addr0 = ip0->dst_address.as_u32;
1796           vnet_buffer (b0)->sw_if_index[VLIB_TX] = s0->in2out.fib_index;
1797
1798           sum0 = ip0->checksum;
1799           sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1800                                  ip4_header_t,
1801                                  dst_address /* changed member */ );
1802           if (PREDICT_FALSE (is_twice_nat_session (s0)))
1803             sum0 = ip_csum_update (sum0, ip0->src_address.as_u32,
1804                                    s0->ext_host_nat_addr.as_u32, ip4_header_t,
1805                                    src_address);
1806           ip0->checksum = ip_csum_fold (sum0);
1807
1808           if (PREDICT_FALSE (ip4_is_first_fragment (ip0)))
1809             {
1810               old_port0 = udp0->dst_port;
1811               new_port0 = udp0->dst_port = s0->in2out.port;
1812
1813               if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
1814                 {
1815                   sum0 = tcp0->checksum;
1816                   sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
1817                                          ip4_header_t,
1818                                          dst_address /* changed member */ );
1819
1820                   sum0 = ip_csum_update (sum0, old_port0, new_port0,
1821                                          ip4_header_t /* cheat */ ,
1822                                          length /* changed member */ );
1823                   if (is_twice_nat_session (s0))
1824                     {
1825                       sum0 = ip_csum_update (sum0, ip0->src_address.as_u32,
1826                                              s0->ext_host_nat_addr.as_u32,
1827                                              ip4_header_t, dst_address);
1828                       sum0 = ip_csum_update (sum0, tcp0->src_port,
1829                                              s0->ext_host_nat_port,
1830                                              ip4_header_t, length);
1831                       tcp0->src_port = s0->ext_host_nat_port;
1832                       ip0->src_address.as_u32 = s0->ext_host_nat_addr.as_u32;
1833                     }
1834                   tcp0->checksum = ip_csum_fold (sum0);
1835                 }
1836               else if (udp0->checksum)
1837                 {
1838                   sum0 = udp0->checksum;
1839                   sum0 =
1840                     ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
1841                                     dst_address);
1842                   sum0 =
1843                     ip_csum_update (sum0, old_port0, new_port0, ip4_header_t,
1844                                     length);
1845                   if (PREDICT_FALSE (is_twice_nat_session (s0)))
1846                     {
1847                       sum0 = ip_csum_update (sum0, ip0->src_address.as_u32,
1848                                              s0->ext_host_nat_addr.as_u32,
1849                                              ip4_header_t, dst_address);
1850                       sum0 = ip_csum_update (sum0, udp0->src_port,
1851                                              s0->ext_host_nat_port,
1852                                              ip4_header_t, length);
1853                       udp0->src_port = s0->ext_host_nat_port;
1854                       ip0->src_address.as_u32 = s0->ext_host_nat_addr.as_u32;
1855                     }
1856                   udp0->checksum = ip_csum_fold (sum0);
1857                 }
1858               else
1859                 {
1860                   if (PREDICT_FALSE (is_twice_nat_session (s0)))
1861                     {
1862                       udp0->src_port = s0->ext_host_nat_port;
1863                       ip0->src_address.as_u32 = s0->ext_host_nat_addr.as_u32;
1864                     }
1865                 }
1866             }
1867
1868           /* Accounting */
1869           nat44_session_update_counters (s0, now,
1870                                          vlib_buffer_length_in_chain (vm, b0),
1871                                          thread_index);
1872           /* Per-user LRU list maintenance */
1873           nat44_session_update_lru (sm, s0, thread_index);
1874
1875         trace0:
1876           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
1877                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
1878             {
1879               nat44_reass_trace_t *t =
1880                 vlib_add_trace (vm, node, b0, sizeof (*t));
1881               t->cached = cached0;
1882               t->sw_if_index = sw_if_index0;
1883               t->next_index = next0;
1884             }
1885
1886           if (cached0)
1887             {
1888               n_left_to_next++;
1889               to_next--;
1890             }
1891           else
1892             {
1893               pkts_processed += next0 != NAT_NEXT_DROP;
1894
1895               /* verify speculative enqueue, maybe switch current next frame */
1896               vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
1897                                                to_next, n_left_to_next,
1898                                                bi0, next0);
1899             }
1900
1901           if (n_left_from == 0 && vec_len (fragments_to_loopback))
1902             {
1903               from = vlib_frame_vector_args (frame);
1904               u32 len = vec_len (fragments_to_loopback);
1905               if (len <= VLIB_FRAME_SIZE)
1906                 {
1907                   clib_memcpy_fast (from, fragments_to_loopback,
1908                                     sizeof (u32) * len);
1909                   n_left_from = len;
1910                   vec_reset_length (fragments_to_loopback);
1911                 }
1912               else
1913                 {
1914                   clib_memcpy_fast (from, fragments_to_loopback +
1915                                     (len - VLIB_FRAME_SIZE),
1916                                     sizeof (u32) * VLIB_FRAME_SIZE);
1917                   n_left_from = VLIB_FRAME_SIZE;
1918                   _vec_len (fragments_to_loopback) = len - VLIB_FRAME_SIZE;
1919                 }
1920             }
1921         }
1922
1923       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
1924     }
1925
1926   vlib_node_increment_counter (vm, sm->ed_out2in_reass_node_index,
1927                                NAT_OUT2IN_ED_ERROR_OUT2IN_PACKETS,
1928                                pkts_processed);
1929
1930   nat_send_all_to_node (vm, fragments_to_drop, node,
1931                         &node->errors[NAT_OUT2IN_ED_ERROR_DROP_FRAGMENT],
1932                         NAT_NEXT_DROP);
1933
1934   vec_free (fragments_to_drop);
1935   vec_free (fragments_to_loopback);
1936   return frame->n_vectors;
1937 }
1938
1939 VLIB_NODE_FN (nat44_ed_out2in_node) (vlib_main_t * vm,
1940                                      vlib_node_runtime_t * node,
1941                                      vlib_frame_t * frame)
1942 {
1943   return nat44_ed_out2in_node_fn_inline (vm, node, frame, 0);
1944 }
1945
1946 /* *INDENT-OFF* */
1947 VLIB_REGISTER_NODE (nat44_ed_out2in_node) = {
1948   .name = "nat44-ed-out2in",
1949   .vector_size = sizeof (u32),
1950   .sibling_of = "nat-default",
1951   .format_trace = format_nat44_ed_out2in_trace,
1952   .type = VLIB_NODE_TYPE_INTERNAL,
1953   .n_errors = ARRAY_LEN(nat_out2in_ed_error_strings),
1954   .error_strings = nat_out2in_ed_error_strings,
1955   .runtime_data_bytes = sizeof (snat_runtime_t),
1956 };
1957 /* *INDENT-ON* */
1958
1959 VLIB_NODE_FN (nat44_ed_out2in_slowpath_node) (vlib_main_t * vm,
1960                                               vlib_node_runtime_t * node,
1961                                               vlib_frame_t * frame)
1962 {
1963   return nat44_ed_out2in_node_fn_inline (vm, node, frame, 1);
1964 }
1965
1966 /* *INDENT-OFF* */
1967 VLIB_REGISTER_NODE (nat44_ed_out2in_slowpath_node) = {
1968   .name = "nat44-ed-out2in-slowpath",
1969   .vector_size = sizeof (u32),
1970   .sibling_of = "nat-default",
1971   .format_trace = format_nat44_ed_out2in_trace,
1972   .type = VLIB_NODE_TYPE_INTERNAL,
1973   .n_errors = ARRAY_LEN(nat_out2in_ed_error_strings),
1974   .error_strings = nat_out2in_ed_error_strings,
1975   .runtime_data_bytes = sizeof (snat_runtime_t),
1976 };
1977 /* *INDENT-ON* */
1978
1979 VLIB_NODE_FN (nat44_ed_out2in_reass_node) (vlib_main_t * vm,
1980                                            vlib_node_runtime_t * node,
1981                                            vlib_frame_t * frame)
1982 {
1983   return nat44_ed_out2in_reass_node_fn_inline (vm, node, frame);
1984 }
1985
1986 /* *INDENT-OFF* */
1987 VLIB_REGISTER_NODE (nat44_ed_out2in_reass_node) = {
1988   .name = "nat44-ed-out2in-reass",
1989   .vector_size = sizeof (u32),
1990   .sibling_of = "nat-default",
1991   .format_trace = format_nat44_reass_trace,
1992   .type = VLIB_NODE_TYPE_INTERNAL,
1993   .n_errors = ARRAY_LEN(nat_out2in_ed_error_strings),
1994   .error_strings = nat_out2in_ed_error_strings,
1995 };
1996 /* *INDENT-ON* */
1997
1998 static u8 *
1999 format_nat_pre_trace (u8 * s, va_list * args)
2000 {
2001   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
2002   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
2003   nat_pre_trace_t *t = va_arg (*args, nat_pre_trace_t *);
2004   return format (s, "out2in next_index %d", t->next_index);
2005 }
2006
2007 VLIB_NODE_FN (nat_pre_out2in_node) (vlib_main_t * vm,
2008                                     vlib_node_runtime_t * node,
2009                                     vlib_frame_t * frame)
2010 {
2011   return nat_pre_node_fn_inline (vm, node, frame,
2012                                  NAT_NEXT_OUT2IN_ED_FAST_PATH);
2013 }
2014
2015 /* *INDENT-OFF* */
2016 VLIB_REGISTER_NODE (nat_pre_out2in_node) = {
2017   .name = "nat-pre-out2in",
2018   .vector_size = sizeof (u32),
2019   .sibling_of = "nat-default",
2020   .format_trace = format_nat_pre_trace,
2021   .type = VLIB_NODE_TYPE_INTERNAL,
2022   .n_errors = 0,
2023  };
2024 /* *INDENT-ON* */
2025
2026 /*
2027  * fd.io coding-style-patch-verification: ON
2028  *
2029  * Local Variables:
2030  * eval: (c-set-style "gnu")
2031  * End:
2032  */